Process for making paper



Jan. 29 1924.

r w. R. HOWARD PROCESS FOR MAKING PAPER Filed Nov. 10 1920 .30 a feltbla Patented 10.11.29, 1924.

UNITED STATES PATENT OFFICE.

w B. HOWARD, OF BALLSTON, NEW YORK. ASSIGNOR TO FRANK L. BELKNAP,

OF CHICAGO, ILLINOIS.

PROCESS FOR MAKING PAPER.

Application filed November 10, 1920. Serial No. 423,015.

To all'wkom it may concern:

Be it known that I, Wnmrm R. HOWARD, a citizen of the United States,residing in the town of Ballston, county of Saratoga, and I State of NewYork, have invented certain new and useful Improvements in Processes forMaking Paper, of which the following is a s ecification. I 4

his invention relates to improvements in 1 .0 a process and apparatusfor making paper containing waterproofing substances, such as aspha t,tar or other bituminous materials.

The salient object of this invention is to 1B treat the felt blanket ofa paper machine, where felt blankets are used, with a solution of someinsulating substance, such as clay or soap in an aqueous vehicle, or anyother substance which forms an insulating coating upon the surface ofthe blanket and prevents the tar, asphalt or other bituminous comositionused in waterproofing the 1 paper om adhering thereto. Figure 1 is aside elevation of the apparatus as appliedto what is commonly known asthe first press of a paper machine.

Fig. 2 is a detail view of the immersion tank with parts broken away.

Referrin to the drawings-1 designates first commonly used on a papermachine for carrying the web, and 2 and 3 are up er and lower ressurerolls respectively is rough which'tlie blanket 1 is driven n a directionas shown by the arrows. After as passing through these press rollers,the blanket, subsequent to travelling over a series of stretching rolls,runs over the guide roller 4. After passing over this guide roller, theblanket is directed into a box or to tank 5 so placed as to extend theentire width of the felt blanket. Within this tank is mounted animmersion roller 6, over which the blanket passes in its travel. Theroller 6 is positioned in the tank so that it is at all times partlyimmersed in the insulating substanoe or fluid which consists of clay,soap or other non-adhesive substances in an aqueous vehicle. From theimmersion tank, the

blanket passes through rollers 7 and 8, which may! be regulated toimpose any desired pressure upon the blanket in order that any desiredamount of the insulatin' liquid may be retained in the blanket. esepressure rollers or squeeze rollers are mounted over the projection ofthe box or tank 5 so that any liquid pressed from the blanket as itpasses between the rollers, will flow back into the tank. The liquidinsulating solution is introduced into the tank 5 through an inlet pipe9 and the de th maintained 1n the tank is controlled by t e overflowpipe 10. It is necessary only to maintain the height of the liquid inthe tank so high that the blanket, in its travel therethrough, will beentirely immersed in the insulating substance.

The operation of the process is as follows: The box or tank, beingfilled to the height of the overflow pipe with a solution of anysuitable mineral soap and water or a mixture of clay in colloidal formin an aqueous vehicle, and the blanket travelling upon the rolls of thepaper machine is directed about the immerslon roll at which time it isthoroughly saturated with this non-adhesive solution. After beingthoroughly saturated, a portion of the liquid is removed from theblanket by means of the pressure rolls previously explained and onlythat amount of the solution retained in the blanket as will be essentialto its counteracting the admission of the sticky bituminouswaterproofing compositions to which it is subjected in the pa er making.

fter being thus treated, the blanket is in condition to receive the webof the waterroofing paper stock and, due. to this insuating substance,will carry and deliver the web without the difficulty of having thesmall particles of asphalt adhere to the blanket.

I claim as my invention: 1. A process of treating the felt blanket of apaper machine consisting in passing the blanket through a mixture ofclay and water whereby the surface of the blanket is insulated againstadhesive substance.

2. A process for insulating the felt blanket of a {paper machine againstadhesive waterroo ng substances consisting in passin'g said lanketthrough an aqueous solution concontaining an insulating substance anddip recting the blanket subsequent to its immersion in the insulatingsubstance through pressure rolls whereby the amount of insulatingsubstance retained in the blanket may be regulated.

4. A process for insulating the felt blanket of a paper machine againstadhesive waterroofing substances consisting in passing said blanketthrough an aqueous solution containing an insulating substance having acolloidal constituent.

WILLIAM R. HOWARD.

